From: Richard Kenner <kenner@vlsi1.ultra.nyu.edu>
Date: Tue, 29 Apr 2003 22:38:09 +0000 (+0000)
Subject: * tree.c (save_expr): Don't fold a COMPONENT_REF.
X-Git-Tag: releases/gcc-3.4.0~6945
X-Git-Url: https://gcc.gnu.org/git/?a=commitdiff_plain;h=84d8756de1f15d0d04a959133930bfc95e3c5acb;p=gcc.git

* tree.c (save_expr): Don't fold a COMPONENT_REF.

From-SVN: r66264
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 589009a8285b..61ec00e07059 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2003-04-29  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
+
+	* tree.c (save_expr): Don't fold a COMPONENT_REF.
+
 2003-04-29  Olivier Hainque <hainque@act-europe.fr>
 
 	* calls.c (expand_call): When modes of target and valreg match,	force
diff --git a/gcc/tree.c b/gcc/tree.c
index ce5e21997b13..7deaa6564098 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -1378,14 +1378,21 @@ tree
 save_expr (expr)
      tree expr;
 {
-  tree t = fold (expr);
-  tree inner = skip_simple_arithmetic (t);
+  tree t = expr;
+  tree inner;
+
+  /* Don't fold a COMPONENT_EXPR: if the operand was a CONSTRUCTOR (the
+     only time it will fold), it can cause problems with PLACEHOLDER_EXPRs
+     in Ada.  Moreover, it isn't at all clear why we fold here at all.  */
+  if (TREE_CODE (t) != COMPONENT_REF)
+    t = fold (t);
 
   /* If the tree evaluates to a constant, then we don't want to hide that
      fact (i.e. this allows further folding, and direct checks for constants).
      However, a read-only object that has side effects cannot be bypassed.
      Since it is no problem to reevaluate literals, we just return the
      literal node.  */
+  inner = skip_simple_arithmetic (t);
   if (TREE_CONSTANT (inner)
       || (TREE_READONLY (inner) && ! TREE_SIDE_EFFECTS (inner))
       || TREE_CODE (inner) == SAVE_EXPR